Having completed the shock work on my 94q, Ive been driving the car some recently. (usually not driven by me)
I have noticed that it has an erratic idle, which "cycles" between about 1000 and 500 rpm and has a period of about one second between peaks. Sound like someone is repeatedly "revving" the engine, albeit to a rather low level
It doesnt happen at all times, but each time I have had the car out for a 10 minute test drive, it has happened at least once. It happens when the car is in Drive, not so much in neutral.
Anyone have any idea on what could result in this behavior.? What do I need to clean or replace now??
Thanks to all
Erratic Idle
Agreed, most likely MAF connector.
Recently I had what felt like MAF trouble again, just like you describe. This time, circumstances suggest bad gas! It came on with a new tank pumped from a very slow (low) tank. Cleaning the MAF contacts simply didn't help this time. I figured I would have to replace the connector this time. Symptoms disappeared with the next tank. Purely circumstantial thinking, I know, but I think I'll avoid slow pumps!
Recently I had what felt like MAF trouble again, just like you describe. This time, circumstances suggest bad gas! It came on with a new tank pumped from a very slow (low) tank. Cleaning the MAF contacts simply didn't help this time. I figured I would have to replace the connector this time. Symptoms disappeared with the next tank. Purely circumstantial thinking, I know, but I think I'll avoid slow pumps!
I think I have the problem identified. There is a hose which exits the spider (plenum) right next to the egr sensor on the driver's side of the engine. The hose is attached to a right angle fitting that is part of the plenum, and bends underneath the plenum.
This hose has a hole in it and if you put your thumb over it, the idle rises and also settles down.
Does anyone know what the name of this hose is?? I think I found it on a diagram and it is part of the pcv system.
It looks to me like I might be able to replace this hose with a lirrle ingenuity and effort without pullling the whole plenum off. It appears to connect to a metal tube just underneath the plenum.
Comments welcome. I wonder how the heck this thing got the hole in it. Its (the hole) actually fairly large, looks as though it was stabbed with a screwdriver or something.
This hose has a hole in it and if you put your thumb over it, the idle rises and also settles down.
Does anyone know what the name of this hose is?? I think I found it on a diagram and it is part of the pcv system.
It looks to me like I might be able to replace this hose with a lirrle ingenuity and effort without pullling the whole plenum off. It appears to connect to a metal tube just underneath the plenum.
Comments welcome. I wonder how the heck this thing got the hole in it. Its (the hole) actually fairly large, looks as though it was stabbed with a screwdriver or something.
I ordered the replacement hose from Scottsdale for a modest price, and was able to easily disonnect the upper, exposed end of the old one, and then simply used a screwdriver blade as a lever and pushed the lower end off the pipe that is goes on just under the plenum.
Getting the new one on was a little tricky, and I still havent go the clamp over the lower end. Need to buy a pair of long neck needle noses or fishook remove pliers to do it, I think...
Anyway, the old one was shot, as though someone had slashed it, and I then cut it open to examine the insides. The inside rubber was very deteriorated---- looks like the original hose could be upgraded somehow to better tolerate the high temperature and oily gas that gets sucked through it.
I noticed in the other thread that Daedulus's photo of the plenum underside is pretty good.
http://home.socal.rr.com/robve...g.htm
Looks like some of the other hoses might be replaceable from above too, with some dexterity and some funny shaped tools
Getting the new one on was a little tricky, and I still havent go the clamp over the lower end. Need to buy a pair of long neck needle noses or fishook remove pliers to do it, I think...
Anyway, the old one was shot, as though someone had slashed it, and I then cut it open to examine the insides. The inside rubber was very deteriorated---- looks like the original hose could be upgraded somehow to better tolerate the high temperature and oily gas that gets sucked through it.
I noticed in the other thread that Daedulus's photo of the plenum underside is pretty good.
http://home.socal.rr.com/robve...g.htm
Looks like some of the other hoses might be replaceable from above too, with some dexterity and some funny shaped tools
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
They lasted over 9 years [on your 94] what more could anyone want. I'm sure one can find silicone racing hose material as a substitute.
By this time it is not optimum to piecewise replace a hose here and there but to replace EVERY rubber hose at one time.......that way you are good to go for the next 6 years without worrying about which one will go next.
The are 5 special long needle nose: straight, 45, 90, round.....not to mention picks and other tools required.
By this time it is not optimum to piecewise replace a hose here and there but to replace EVERY rubber hose at one time.......that way you are good to go for the next 6 years without worrying about which one will go next.
The are 5 special long needle nose: straight, 45, 90, round.....not to mention picks and other tools required.